Synthesis and characterization of some uranyl and zirconyl nitrilotriacetic acid (NTA) chelates

Four new complexes [UO2(HNTA)(H2O)] center dot 3H(2)O, Na[UO2(NTA)] center dot (H2O), [ZrO(HNTA) (H2O)] center dot 3H(2)O and Na[ZrO(NTA)] center dot H2O were obtained by the reactions of UO22+ and ZrO2+ salts with nitrilotriacetic acid ( NTA) dissolved in water and NaOH aqueous solution. Infrared spectra of the solid complexes have been obtained and assigned on the basis of C-s symmetry. Octahedral and polymeric chain structures are adopted for the uranyl and zirconyl NTA complexes, respectively. Thermogravimetric (TG) and differential thermal analysis (DTA) data are in accordance with the proposed structures and show that the complexes decompose to metal oxides.